Under the rule of the Taliban, foreigners who preach Christianity faced jail time and expulsion. Sixteen Afghans who were allegedly converted by Mercer and her associates faced the death penalty unless they do not renounce Christianity.
Mercer and another American, Dayna Curry, were working for a German-based Christian group called Shelter Now International. The Taliban had raided the group's offices in August 2001 and arrested Mercer and the others. Taliban officials said they found evidence of proselytizing, including Bibles in local languages.
A 1995 graduate of Madison High School in Vienna, Virginia, where she was a track captain and a leader of the school's Fellowship of Christian Athletes.
In her high school yearbook, Mercer quoted Isaiah 40: "Those who hope in the Lord will renew their strength. They will soar on wings like eagles. ... They will walk and not be faint."
After high school, Mercer attended Baylor University, majored in German and became heavily involved at Antioch Community Church in Waco, Texas.